In the telephone loop plant today, telephone loops are terminated on remote telephone switches or remote terminals of carrier systems or concentrators. The remote switch, however, obtains control for many of its functions from a host telephone switch to which it is connected via a carrier system; both remote switch and host switch are typcially electronic switches. In order to perform certain tests on the telephone loops, however, a metallic path is provided between the test apparatus which is located at the host switch, and the remote switch, bypassing the carrier system.
When the remote switch is located beyond a predetermined distance, tests may not be conducted over the aforesaid metallic path. In such cases, it is desirable to locate the test apparatus remotely from the host switch so that the distance between the test apparatus and the station apparatus at the end of the telephone loop falls below the aforesaid predetermined distance. Additionally, it is necessary to devise a method for permitting the test apparatus to access the telephone loops.